i want to display data according to type in same query - sql

i have following table "vehicle_data" :
ID ALERT_TYPE VALUE
58 2 1
58 1 1
104 1 1
104 2 1
Here alert_type = 2 is for GPS value and alert_type=1 is for engine_value .
so if alert_type=2 and its value is =1 then it means its value is correct.
when alert_type=2 and its value is =0 then it means its value is wrong.
same for alert_type=1
so now here i want the following output:
ID gps engine_value
58 1 1
104 1 1
how can i perform this query??

You can do it like this.
SELECT ID
,CASE WHEN [ALERT_TYPE]=2 and [value ]=1 THEN 1 ELSE 0 END as gps
,CASE WHEN [ALERT_TYPE]=1 and [value ]=1 THEN 1 ELSE 0 END as engine
FROM vehicle_data

SELECT ID, alert_type=2 AS gps, alert_type=1 AS [engine] FROM vehicle_data WHERE value=1;
EDITED to account for your explanation of VALUE.

Schema
CREATE TABLE table3 (id int, ALERT_TYPE int)
INSERT table3 VALUES (58, 1), (58, 2), (104, 1), (104, 2)
Query
SELECT *
FROM (
SELECT ID
,ROW_NUMBER() OVER (
PARTITION BY id ORDER BY id
) AS row_num
,gps = CASE
WHEN ALERT_TYPE = 2
THEN 1
ELSE 0
END
,engine = CASE
WHEN ALERT_TYPE = 1
THEN 1
ELSE 0
END
FROM table3
) a
WHERE a.row_num = 1
Output
ID gps engine
58 1 0
104 0 1

One possible way using subqueries :
select
Ids.ID
, gps.VALUE 'gps'
, engine_value.VALUE 'engine_value'
from (select distinct ID from vehicle_data) Ids
left join
(select ID, VALUE from vehicle_data where ALERT_TYPE = 2) gps
on gps.ID = Ids.ID
left join
(select ID, VALUE from vehicle_data where ALERT_TYPE = 1) engine_value
on engine_value.ID = Ids.ID
[SQL Fiddle demo]

I hope this should work for you,
Select ID,sum(gps) as gps ,sum(engine) as engine from
(SELECT ID
,CASE WHEN [ALERT_TYPE]=2 and [value ]=1 THEN 1 ELSE 0 END as gps
,CASE WHEN [ALERT_TYPE]=1 and [value ]=1 THEN 1 ELSE 0 END as engine
FROM vehicle_data
)a
group by id

select x.id,x.alert_type as GPS,x.value as engine_value from (
select ID,alert_type,value,ROW_NUMBER() over (partition by id order by alert_type ) as Rnk from mytable
)x
where Rnk=1

Please check this query in SQL :
create table mytable (id int, alert_type int, value int);
insert into mytable (id, alert_type, value)
values (58, 2, 1),
(58, 1, 1),
(104, 1, 1),
(104, 2, 1);
SELECT distinct ID
,(select count (id) from mytable mt where mt.id=mytable.id and mt.[ALERT_TYPE]=2 and mt.[value ]=1) as gps
,(select count (id) from mytable mt where mt.id=mytable.id and mt.[ALERT_TYPE]=1 and mt.[value ]=1) as engine
FROM mytable

BASED ON YOUR QUESTION I BELIEVE YOU WANT THE DATA IN COLUMN AND TO SUIT YOUR REQUIREMENT I HAVE MADE A SQL FIDDLE WORKING - CODE IS ALSO MENTIONED BELOW -
HERE YOU GO WITH THE WORKING FIDDLE -
WORKING DEMO
SQL CODE FOR REFERNECE -
CREATE TABLE ALERTS (ID INT, ALERT_TYPE INT, VALUE INT)
INSERT INTO ALERTS VALUES (58,2,1)
INSERT INTO ALERTS VALUES (58,1,0)
INSERT INTO ALERTS VALUES (104,1,1)
INSERT INTO ALERTS VALUES (104,2,0)
CREATE TABLE ALERTSVALUE (ID INT, gps INT,engine INT)
INSERT INTO ALERTSVALUE VALUES (58,1,0)
INSERT INTO ALERTSVALUE VALUES (104,0,1)
SELECT A.ID,
CASE A.ALERT_TYPE WHEN 2 THEN 1 ELSE 0 END AS GPS,
CASE A.ALERT_TYPE WHEN 1 THEN 1 ELSE 0 END AS ENGINE_VALUE,
A.VALUE FROM ALERTS A WHERE A.VALUE = 1
EDIT BASED ON COMMENT - TO MERGE THE ROWS FOR BOTH GPS AND ENGINE_VALUE:
SELECT X.ID,X.ALERT_TYPE as GPS,X.VALUE as ENGINE_VALUE
FROM (
SELECT ID,ALERT_TYPE ,VALUE ,ROW_NUMBER() OVER (PARTITION BY ID ORDER BY alert_type ) AS [Rank] FROM ALERTS
)X
WHERE [Rank]=1
SQL FIDDLE DEMO

Related

Select first occurrence of value after last occurrence of other value in SQL

I have a requirement to find the current operation of a part. The table I have to get this information from lists operation statuses of complete (1) or 0. So the table typically looks like:
ID Operation Status
1 100 1
2 200 1
3 250 1
4 300 0
5 350 0
So in this case Operation 300 is the current op which I get using MIN(Operation) WHERE Status = 0.
However, some cases have appeared where some operations are skipped which would look like:
ID Operation Status
1 100 1
2 200 0
3 250 1
4 300 0
5 350 0
So in this case the current operation is still Operation 300 but MIN(Operation) doesn't work. What I need is the first occurrence of the row where Status = 0 that follows the last occurrence of a Status = 1 row. How could I achieve this?
Edit: Also have to consider the case where all operations are Status 0, where the correct result would be the first row (Operation 100)
This will give you the entire row to work with:
DECLARE #MyTable TABLE (
ID INT,
Operation INT,
Status BIT
);
INSERT INTO #MyTable VALUES
(1, 100, 1)
,(2, 200, 0)
,(3, 250, 1)
,(4, 300, 0)
,(5, 350, 0)
;
WITH MaxOperation AS (
SELECT MAX(x.Operation) AS MaxOperation
FROM #MyTable x
WHERE x.Status = 1
)
SELECT TOP 1 t.*
FROM #MyTable t
CROSS APPLY (SELECT MaxOperation FROM MaxOperation) x
WHERE t.Operation > x.MaxOperation
OR x.MaxOperation IS NULL
ORDER BY t.Operation
This will result in:
ID Operation Status
----------- ----------- ------
4 300 0
It will also produce this if all the Status values are 0:
ID Operation Status
----------- ----------- ------
1 100 0
I'm sure there is a clever window function way to do it, but in vanilla sql this is the idea
SELECT MIN(Operation)
FROM SOME_TABLE
WHERE Operation >
( SELECT MAX(Operation)
FROM SOME_TABLE
WHERE status = 1
)
As indicated by user Error_2646, a good way would be something like
select
min(ID)
from
[YourTable]
where
ID > (select max(ID) from [YourTable] where Status = 1)
I hope this answer will give you the correct answer. If you can add the expected output in a image it is more easy to identify what you need. Please add schema and data when, so that it is easy for user to put their solutions.
Schema and data I used:
(
ID INT
,operation INT
,Status INT
)
insert into Occurances values(1,100,1)
insert into Occurances values(2,200,0)
insert into Occurances values(1,250,1)
insert into Occurances values(1,300,0)
insert into Occurances values(1,350,0)
SELECT *
FROM
(
SELECT
Rank() OVER ( ORDER BY operation) AS [rank]
,MIN([operation]) AS [min]
,id
,[status]
FROM Occurances
WHERE [Status]= 0
GROUP BY id
,[status]
,operation
UNION
SELECT
Rank() OVER ( ORDER BY operation DESC) AS [rank]
,MAX([operation]) AS [min]
,id
,[status]
FROM Occurances
WHERE [Status]= 1
GROUP BY id
,[status]
,operation
) AS A
WHERE A.[rank]= 1
This is the answer I am getting:
You can do this very efficiently with a window function:
SELECT TOP (1) *
FROM (
SELECT *, LEAD(Status) OVER (ORDER BY Operation DESC) AS PreviousStatus
FROM myTable
)
WHERE Status = 0 AND PreviousStatus = 1
ORDER BY Operation DESC
Try this:
DECLARE #Table TABLE
(
ID int
, Operation int
, [Status] bit
)
;
INSERT INTO #Table (ID, Operation, [Status])
VALUES
(1, 100, 1)
, (2, 200, 0)
, (3, 250, 1)
, (4, 300, 1)
, (5, 350, 0)
;
SELECT TOP 1 T.*
FROM #Table T
WHERE T.[Status] = 0
AND T.ID > (
SELECT TOP 1 T.ID
FROM #Table T
WHERE T.[Status] = 1
ORDER BY ID DESC
)
ORDER BY ID

How to get the result in below format in SQL Server?

I have a table called recipes with following data.
page_no title
-----------------
1 pancake
2 pizza
3 pasta
5 cookie
page_no 0 is always blank, and missing page_no are blank, I want output as below, for the blank page NULL values in the result.
left_title right_title
------------------------
NULL pancake
Pizza pasta
NULL cookie
I have tried this SQL statement, but it's not returning the desired output:
SELECT
CASE WHEN id % 2 = 0
THEN title
END AS left_title,
CASE WHEN id %2 != 0
THEN title
END AS right_title
FROM
recipes
You are quite close. You just need aggregation:
select max(case when id % 2 = 0 then title end) as left_title,
max(case when id % 2 = 1 then title end) as right_title
from recipes
group by id / 2
order by min(id);
SQL Server does integer division, so id / 2 is always an integer.
Using CTE.. this should be give you a good CTE overview
DECLARE #table TABLE (
pageno int,
title varchar(30)
)
INSERT INTO #table
VALUES (1, 'pancake')
, (2, 'pizza')
, (3, 'pasta')
, (5, 'cookie')
;
WITH cte_pages
AS ( -- generate page numbers
SELECT
0 n,
MAX(pageno) maxpgno
FROM #table
UNION ALL
SELECT
n + 1 n,
maxpgno
FROM cte_pages
WHERE n <= maxpgno),
cte_left
AS ( --- even
SELECT
n,
ROW_NUMBER() OVER (ORDER BY n) rn
FROM cte_pages
WHERE n % 2 = 0),
cte_right
AS ( --- odd
SELECT
n,
ROW_NUMBER() OVER (ORDER BY n) rn
FROM cte_pages
WHERE n % 2 <> 0)
SELECT
tl.title left_title,
tr.title right_title --- final output
FROM cte_left l
INNER JOIN cte_right r
ON l.rn = r.rn
LEFT OUTER JOIN #table tl
ON tl.pageno = l.n
LEFT OUTER JOIN #table tr
ON tr.pageno = r.n

SQL Anywhere: find rows that are +-2 compared to another row

I have the following table:
ID User Form Depth
1 A ABC 2001
1 A XYZ 1001
1 B XYZ 1003
1 B DEF 3001
1 C XYZ 1000
If ID and Form are identical, I need to identify those rows that are +-2 from User A. Using the example above, the script would return:
ID User Form Depth
1 B XYZ 1003
1 C XYZ 1000
I already have a script which identifies rows with identical ID and Form--I just need the other part, but I'm struggling with figuring out the logic. I was hoping there was some kind of DIFF function I could use, but I can't find one for SQL Anywhere.
Does anyone have any suggestions?
Thanks!
If you're looking for the depth to be exactly +/-2 from A's depth:
select t1.*
from mytab t1,
mytab t2
where t1.id = t2.id
and t1.form = t2.form
and t1.user != 'A'
and t2.user = 'A'
and abs(t1.depth - t2.depth) = 2
go
ID User Form Depth
--- ----- ----- -----
1 B XYZ 1003
If you're looking for the depth to be within 2 of A's depth (ie, diff <= 2):
select t1.*
from mytab t1,
mytab t2
where t1.id = t2.id
and t1.form = t2.form
and t1.user != 'A'
and t2.user = 'A'
and abs(t1.depth - t2.depth) <= 2
go
ID User Form Depth
--- ----- ----- -----
1 B XYZ 1003
1 C XYZ 1000
This is pretty basic SQL so while this fiddle was done with MySQL, you should find the queries work in SQLAnywhere, too: sql fiddle
I think you want exists:
select t.*
from t
where t.user <> 'A' and
exists (select 1
from t t2
where t2.form = t.form and t2.id = t.id and
t2.depth between t.depth - 2 and t.depth + 2
);
A quick and dirty generalized method.
Replace #User with whomever you would like to remove.
DECLARE #table TABLE (
ID Int
,[User] VARCHAR(2)
,Form VARCHAR(3)
,Depth INT
)
DECLARE #User VARCHAR(2) = 'A'
INSERT INTO #table (ID , [User], Form, Depth)
VALUES
(1 , 'A' , 'ABC' , 2001),
(1 , 'A' , 'XYZ' , 1001),
(1 , 'B' , 'XYZ' , 1003),
(1 , 'B' , 'DEF' , 3001),
(1 , 'C' , 'XYZ' , 1000)
SELECT t1.ID, t1.[User], t1.Form, t1.Depth , ROW_NUMBER() OVER(ORDER BY t1.ID, t1.[User], t1.Form, t1.Depth) AS [row_number]
INTO #temp
FROM #table as t1
INNER JOIN (
SELECT t.ID, t.Form, COUNT('8') as [count]
FROM #table as t
GROUP BY ID, Form
HAVING COUNT('8') > 1
) as duplicates
ON duplicates.ID = t1.ID
AND duplicates. Form = t1.Form
ORDER BY ID, User, Form, Depth
-- SELECT * FROM #temp
SELECT [row_number] - 2 as value
INTO #range
FROM #temp as t
WHERE t.[User] = #User
--SELECT * FROM #range
INSERT INTO #range
SELECT [row_number] - 1
FROM #temp as t
WHERE t.[User] = #User
INSERT INTO #range
SELECT [row_number] + 1
FROM #temp as t
WHERE t.[User] = #User
INSERT INTO #range
SELECT [row_number] + 2
FROM #temp as t
WHERE t.[User] = #User
SELECT * FROM #temp
WHERE [row_number] IN (SELECT value FROM #range)
DROP TABLE #temp
DROP TABLE #range

Sql Partitioning

I have Sql Table data and i need to filter only the Consecutive dates blocks as i highlighted on image below..
.
and i need to add custom rates for each row on that selected blocks(this rate can display with separate column on out put).If there is more than 6 rows captured then $200 apply for each column of that block.if it is less than 6 ,it will be $125.The out put should be like this
And it should group by EmpID.
i need to get the out put using MSSQL. Can any one help me
this is what i have done through the sql view
ALTER view [dbo].[vw_Test2] AS
SELECT
tbl2.ID as Tbl2ID,
tbl1.[EmpID],
tbl1.[ExpInDateTime] as Tbl1ExpDate,
tbl2.[ExpInDateTime] as Tbl2ExpDate,
case when(CONVERT(date,tbl1.[ActInDateTime]) = CONVERT(date, DATEADD(DAY,1,tbl2.[ExpInDateTime]))) then
1
else 0
end as Token
from [dbo].[vw_Test] tbl1 join [dbo].[vw_Test] tbl2
on tbl1.ID=(tbl2.ID+1)
GO
only thing is i have to do this using SQL views
Please try this as a view:
ALTER VIEW [dbo].[vw_Test2] AS
WITH PreResult AS (
SELECT p.Id,p.EmpID,p.[DateTime],CASE WHEN LEAD(p.diff)OVER(ORDER BY p.Id) > 1 OR LEAD(p.EmpID)OVER(ORDER BY p.Id)<>p.EmpID THEN 1 ELSE 0 END StartNewGroup
FROM (
SELECT t.Id,t.EmpID,t.[DateTime], COALESCE(DATEDIFF(day,LAG(t.[DateTime])OVER(PARTITION BY t.EmpID ORDER BY t.Id),t.[DateTime]),1) [diff]
FROM [dbo].[vw_Test] t
) p
)
SELECT r.Id,r.EmpID,r.[DateTime]
,CASE WHEN COUNT(*)OVER(PARTITION BY r.NewGroup ORDER BY r.NewGroup) >= 6 THEN 250 ELSE 125 END [Rate]
FROM (
SELECT b.Id,b.EmpID,b.[DateTime],1+COALESCE((SELECT SUM(a.StartNewGroup) FROM PreResult a WHERE a.Id<b.Id),0) NewGroup
FROM PreResult b
) r
GO
There is also query to play with:
CREATE TABLE #Test (Id BIGINT IDENTITY(1,1),EmpID BIGINT, [DateTime] DATETIME)
INSERT INTO #Test (EmpID,[DateTime]) VALUES (5,'20150106'),(5,'20150107'),(5,'20150109'),
(5,'20150110'),(5,'20150126'),(5,'20150127'),
(5,'20150128'),(5,'20150129'),(5,'20150130'),
(5,'20150131'),(10,'20121203'),(10,'20121204'),
(10,'20121205'),(10,'20121206'),
(10,'20121207'),(10,'20121208'),(10,'20121209')
;WITH PreResult AS (
SELECT p.Id,p.EmpID,p.[DateTime],CASE WHEN LEAD(p.diff)OVER(ORDER BY p.Id) > 1 OR LEAD(p.EmpID)OVER(ORDER BY p.Id)<>p.EmpID THEN 1 ELSE 0 END StartNewGroup
FROM (
SELECT t.Id,t.EmpID,t.[DateTime], COALESCE(DATEDIFF(day,LAG(t.[DateTime])OVER(PARTITION BY t.EmpID ORDER BY t.Id),t.[DateTime]),1) [diff]
FROM #Test t
) p
)
SELECT r.Id,r.EmpID,r.[DateTime]
,CASE WHEN COUNT(*)OVER(PARTITION BY r.NewGroup ORDER BY r.NewGroup) >= 6 THEN 250 ELSE 125 END [Rate]
FROM (
SELECT b.Id,b.EmpID,b.[DateTime],1+COALESCE((SELECT SUM(a.StartNewGroup) FROM PreResult a WHERE a.Id<b.Id),0) NewGroup
FROM PreResult b
) r
DROP TABLE #Test
Please let me know if you have any questions.

How do I find a "gap" in running counter with SQL?

I'd like to find the first "gap" in a counter column in an SQL table. For example, if there are values 1,2,4 and 5 I'd like to find out 3.
I can of course get the values in order and go through it manually, but I'd like to know if there would be a way to do it in SQL.
In addition, it should be quite standard SQL, working with different DBMSes.
In MySQL and PostgreSQL:
SELECT id + 1
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
ORDER BY
id
LIMIT 1
In SQL Server:
SELECT TOP 1
id + 1
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
ORDER BY
id
In Oracle:
SELECT *
FROM (
SELECT id + 1 AS gap
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
ORDER BY
id
)
WHERE rownum = 1
ANSI (works everywhere, least efficient):
SELECT MIN(id) + 1
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
Systems supporting sliding window functions:
SELECT -- TOP 1
-- Uncomment above for SQL Server 2012+
previd
FROM (
SELECT id,
LAG(id) OVER (ORDER BY id) previd
FROM mytable
) q
WHERE previd <> id - 1
ORDER BY
id
-- LIMIT 1
-- Uncomment above for PostgreSQL
Your answers all work fine if you have a first value id = 1, otherwise this gap will not be detected. For instance if your table id values are 3,4,5, your queries will return 6.
I did something like this
SELECT MIN(ID+1) FROM (
SELECT 0 AS ID UNION ALL
SELECT
MIN(ID + 1)
FROM
TableX) AS T1
WHERE
ID+1 NOT IN (SELECT ID FROM TableX)
There isn't really an extremely standard SQL way to do this, but with some form of limiting clause you can do
SELECT `table`.`num` + 1
FROM `table`
LEFT JOIN `table` AS `alt`
ON `alt`.`num` = `table`.`num` + 1
WHERE `alt`.`num` IS NULL
LIMIT 1
(MySQL, PostgreSQL)
or
SELECT TOP 1 `num` + 1
FROM `table`
LEFT JOIN `table` AS `alt`
ON `alt`.`num` = `table`.`num` + 1
WHERE `alt`.`num` IS NULL
(SQL Server)
or
SELECT `num` + 1
FROM `table`
LEFT JOIN `table` AS `alt`
ON `alt`.`num` = `table`.`num` + 1
WHERE `alt`.`num` IS NULL
AND ROWNUM = 1
(Oracle)
The first thing that came into my head. Not sure if it's a good idea to go this way at all, but should work. Suppose the table is t and the column is c:
SELECT
t1.c + 1 AS gap
FROM t as t1
LEFT OUTER JOIN t as t2 ON (t1.c + 1 = t2.c)
WHERE t2.c IS NULL
ORDER BY gap ASC
LIMIT 1
Edit: This one may be a tick faster (and shorter!):
SELECT
min(t1.c) + 1 AS gap
FROM t as t1
LEFT OUTER JOIN t as t2 ON (t1.c + 1 = t2.c)
WHERE t2.c IS NULL
This works in SQL Server - can't test it in other systems but it seems standard...
SELECT MIN(t1.ID)+1 FROM mytable t1 WHERE NOT EXISTS (SELECT ID FROM mytable WHERE ID = (t1.ID + 1))
You could also add a starting point to the where clause...
SELECT MIN(t1.ID)+1 FROM mytable t1 WHERE NOT EXISTS (SELECT ID FROM mytable WHERE ID = (t1.ID + 1)) AND ID > 2000
So if you had 2000, 2001, 2002, and 2005 where 2003 and 2004 didn't exist, it would return 2003.
The following solution:
provides test data;
an inner query that produces other gaps; and
it works in SQL Server 2012.
Numbers the ordered rows sequentially in the "with" clause and then reuses the result twice with an inner join on the row number, but offset by 1 so as to compare the row before with the row after, looking for IDs with a gap greater than 1. More than asked for but more widely applicable.
create table #ID ( id integer );
insert into #ID values (1),(2), (4),(5),(6),(7),(8), (12),(13),(14),(15);
with Source as (
select
row_number()over ( order by A.id ) as seq
,A.id as id
from #ID as A WITH(NOLOCK)
)
Select top 1 gap_start from (
Select
(J.id+1) as gap_start
,(K.id-1) as gap_end
from Source as J
inner join Source as K
on (J.seq+1) = K.seq
where (J.id - (K.id-1)) <> 0
) as G
The inner query produces:
gap_start gap_end
3 3
9 11
The outer query produces:
gap_start
3
Inner join to a view or sequence that has a all possible values.
No table? Make a table. I always keep a dummy table around just for this.
create table artificial_range(
id int not null primary key auto_increment,
name varchar( 20 ) null ) ;
-- or whatever your database requires for an auto increment column
insert into artificial_range( name ) values ( null )
-- create one row.
insert into artificial_range( name ) select name from artificial_range;
-- you now have two rows
insert into artificial_range( name ) select name from artificial_range;
-- you now have four rows
insert into artificial_range( name ) select name from artificial_range;
-- you now have eight rows
--etc.
insert into artificial_range( name ) select name from artificial_range;
-- you now have 1024 rows, with ids 1-1024
Then,
select a.id from artificial_range a
where not exists ( select * from your_table b
where b.counter = a.id) ;
This one accounts for everything mentioned so far. It includes 0 as a starting point, which it will default to if no values exist as well. I also added the appropriate locations for the other parts of a multi-value key. This has only been tested on SQL Server.
select
MIN(ID)
from (
select
0 ID
union all
select
[YourIdColumn]+1
from
[YourTable]
where
--Filter the rest of your key--
) foo
left join
[YourTable]
on [YourIdColumn]=ID
and --Filter the rest of your key--
where
[YourIdColumn] is null
For PostgreSQL
An example that makes use of recursive query.
This might be useful if you want to find a gap in a specific range
(it will work even if the table is empty, whereas the other examples will not)
WITH
RECURSIVE a(id) AS (VALUES (1) UNION ALL SELECT id + 1 FROM a WHERE id < 100), -- range 1..100
b AS (SELECT id FROM my_table) -- your table ID list
SELECT a.id -- find numbers from the range that do not exist in main table
FROM a
LEFT JOIN b ON b.id = a.id
WHERE b.id IS NULL
-- LIMIT 1 -- uncomment if only the first value is needed
My guess:
SELECT MIN(p1.field) + 1 as gap
FROM table1 AS p1
INNER JOIN table1 as p3 ON (p1.field = p3.field + 2)
LEFT OUTER JOIN table1 AS p2 ON (p1.field = p2.field + 1)
WHERE p2.field is null;
I wrote up a quick way of doing it. Not sure this is the most efficient, but gets the job done. Note that it does not tell you the gap, but tells you the id before and after the gap (keep in mind the gap could be multiple values, so for example 1,2,4,7,11 etc)
I'm using sqlite as an example
If this is your table structure
create table sequential(id int not null, name varchar(10) null);
and these are your rows
id|name
1|one
2|two
4|four
5|five
9|nine
The query is
select a.* from sequential a left join sequential b on a.id = b.id + 1 where b.id is null and a.id <> (select min(id) from sequential)
union
select a.* from sequential a left join sequential b on a.id = b.id - 1 where b.id is null and a.id <> (select max(id) from sequential);
https://gist.github.com/wkimeria/7787ffe84d1c54216f1b320996b17b7e
Here is an alternative to show the range of all possible gap values in portable and more compact way :
Assume your table schema looks like this :
> SELECT id FROM your_table;
+-----+
| id |
+-----+
| 90 |
| 103 |
| 104 |
| 118 |
| 119 |
| 120 |
| 121 |
| 161 |
| 162 |
| 163 |
| 185 |
+-----+
To fetch the ranges of all possible gap values, you have the following query :
The subquery lists pairs of ids, each of which has the lowerbound column being smaller than upperbound column, then use GROUP BY and MIN(m2.id) to reduce number of useless records.
The outer query further removes the records where lowerbound is exactly upperbound - 1
My query doesn't (explicitly) output the 2 records (YOUR_MIN_ID_VALUE, 89) and (186, YOUR_MAX_ID_VALUE) at both ends, that implicitly means any number in both of the ranges hasn't been used in your_table so far.
> SELECT m3.lowerbound + 1, m3.upperbound - 1 FROM
(
SELECT m1.id as lowerbound, MIN(m2.id) as upperbound FROM
your_table m1 INNER JOIN your_table
AS m2 ON m1.id < m2.id GROUP BY m1.id
)
m3 WHERE m3.lowerbound < m3.upperbound - 1;
+-------------------+-------------------+
| m3.lowerbound + 1 | m3.upperbound - 1 |
+-------------------+-------------------+
| 91 | 102 |
| 105 | 117 |
| 122 | 160 |
| 164 | 184 |
+-------------------+-------------------+
select min([ColumnName]) from [TableName]
where [ColumnName]-1 not in (select [ColumnName] from [TableName])
and [ColumnName] <> (select min([ColumnName]) from [TableName])
Here is standard a SQL solution that runs on all database servers with no change:
select min(counter + 1) FIRST_GAP
from my_table a
where not exists (select 'x' from my_table b where b.counter = a.counter + 1)
and a.counter <> (select max(c.counter) from my_table c);
See in action for;
PL/SQL via Oracle's livesql,
MySQL via sqlfiddle,
PostgreSQL via sqlfiddle
MS Sql via sqlfiddle
It works for empty tables or with negatives values as well. Just tested in SQL Server 2012
select min(n) from (
select case when lead(i,1,0) over(order by i)>i+1 then i+1 else null end n from MyTable) w
If You use Firebird 3 this is most elegant and simple:
select RowID
from (
select `ID_Column`, Row_Number() over(order by `ID_Column`) as RowID
from `Your_Table`
order by `ID_Column`)
where `ID_Column` <> RowID
rows 1
-- PUT THE TABLE NAME AND COLUMN NAME BELOW
-- IN MY EXAMPLE, THE TABLE NAME IS = SHOW_GAPS AND COLUMN NAME IS = ID
-- PUT THESE TWO VALUES AND EXECUTE THE QUERY
DECLARE #TABLE_NAME VARCHAR(100) = 'SHOW_GAPS'
DECLARE #COLUMN_NAME VARCHAR(100) = 'ID'
DECLARE #SQL VARCHAR(MAX)
SET #SQL =
'SELECT TOP 1
'+#COLUMN_NAME+' + 1
FROM '+#TABLE_NAME+' mo
WHERE NOT EXISTS
(
SELECT NULL
FROM '+#TABLE_NAME+' mi
WHERE mi.'+#COLUMN_NAME+' = mo.'+#COLUMN_NAME+' + 1
)
ORDER BY
'+#COLUMN_NAME
-- SELECT #SQL
DECLARE #MISSING_ID TABLE (ID INT)
INSERT INTO #MISSING_ID
EXEC (#SQL)
--select * from #MISSING_ID
declare #var_for_cursor int
DECLARE #LOW INT
DECLARE #HIGH INT
DECLARE #FINAL_RANGE TABLE (LOWER_MISSING_RANGE INT, HIGHER_MISSING_RANGE INT)
DECLARE IdentityGapCursor CURSOR FOR
select * from #MISSING_ID
ORDER BY 1;
open IdentityGapCursor
fetch next from IdentityGapCursor
into #var_for_cursor
WHILE ##FETCH_STATUS = 0
BEGIN
SET #SQL = '
DECLARE #LOW INT
SELECT #LOW = MAX('+#COLUMN_NAME+') + 1 FROM '+#TABLE_NAME
+' WHERE '+#COLUMN_NAME+' < ' + cast( #var_for_cursor as VARCHAR(MAX))
SET #SQL = #sql + '
DECLARE #HIGH INT
SELECT #HIGH = MIN('+#COLUMN_NAME+') - 1 FROM '+#TABLE_NAME
+' WHERE '+#COLUMN_NAME+' > ' + cast( #var_for_cursor as VARCHAR(MAX))
SET #SQL = #sql + 'SELECT #LOW,#HIGH'
INSERT INTO #FINAL_RANGE
EXEC( #SQL)
fetch next from IdentityGapCursor
into #var_for_cursor
END
CLOSE IdentityGapCursor;
DEALLOCATE IdentityGapCursor;
SELECT ROW_NUMBER() OVER(ORDER BY LOWER_MISSING_RANGE) AS 'Gap Number',* FROM #FINAL_RANGE
Found most of approaches run very, very slow in mysql. Here is my solution for mysql < 8.0. Tested on 1M records with a gap near the end ~ 1sec to finish. Not sure if it fits other SQL flavours.
SELECT cardNumber - 1
FROM
(SELECT #row_number := 0) as t,
(
SELECT (#row_number:=#row_number+1), cardNumber, cardNumber-#row_number AS diff
FROM cards
ORDER BY cardNumber
) as x
WHERE diff >= 1
LIMIT 0,1
I assume that sequence starts from `1`.
If your counter is starting from 1 and you want to generate first number of sequence (1) when empty, here is the corrected piece of code from first answer valid for Oracle:
SELECT
NVL(MIN(id + 1),1) AS gap
FROM
mytable mo
WHERE 1=1
AND NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
AND EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = 1
)
DECLARE #Table AS TABLE(
[Value] int
)
INSERT INTO #Table ([Value])
VALUES
(1),(2),(4),(5),(6),(10),(20),(21),(22),(50),(51),(52),(53),(54),(55)
--Gaps
--Start End Size
--3 3 1
--7 9 3
--11 19 9
--23 49 27
SELECT [startTable].[Value]+1 [Start]
,[EndTable].[Value]-1 [End]
,([EndTable].[Value]-1) - ([startTable].[Value]) Size
FROM
(
SELECT [Value]
,ROW_NUMBER() OVER(PARTITION BY 1 ORDER BY [Value]) Record
FROM #Table
)AS startTable
JOIN
(
SELECT [Value]
,ROW_NUMBER() OVER(PARTITION BY 1 ORDER BY [Value]) Record
FROM #Table
)AS EndTable
ON [EndTable].Record = [startTable].Record+1
WHERE [startTable].[Value]+1 <>[EndTable].[Value]
If the numbers in the column are positive integers (starting from 1) then here is how to solve it easily. (assuming ID is your column name)
SELECT TEMP.ID
FROM (SELECT ROW_NUMBER() OVER () AS NUM FROM 'TABLE-NAME') AS TEMP
WHERE ID NOT IN (SELECT ID FROM 'TABLE-NAME')
ORDER BY 1 ASC LIMIT 1
SELECT ID+1 FROM table WHERE ID+1 NOT IN (SELECT ID FROM table) ORDER BY 1;